Plug for oil and gas wells.



WITNESSES H. L. MOLAUGHLIN.

PLUG FOR OIL AND GAS WELLS. APPLIUATION FILED 1156.19. 1912.

Patented Jan. 14, 1913.

2 SHEETS-SHEET 1.

/Ql g INVENTOR JL '/17 Z/mg/l/M,

ATTORNEYS H. L. MGLAUGHLIN.

PLUG FOR OIL AND GAS WELLS.

APPLICATION FILED AUG,19, 1912.

1,050,557, Patented Jan.14,1913.

2 SHEETS-SHEET 2.

ATTORNEYS HUGH L. McLAUGI-ILIN, OF CLEVELAND, OKLAHOMA.

PLUG FOR OIL AND GAS WELLS.

Specification of Letters Patent.

Application led August 19, 1912.

Patented Jan. 14., 1913. Serial No. 715,818.

To all whom it may concern Be it known that I, HUGH L. l\1oL.\UGH LIN, acitizen of the United States of America, residing at Cleveland, in thecounty of Pawnee and State of Oklahoma, have invented certain new anduseful Improvements in Plugs for Oil and Gas Wells, of which thefollowing is a specification, reference being had therein to theaccompanying drawing.

This invention relates to a plug for oil and gas wells, and is used inthe oil and gas elds to plug a well casing or tubing, whereby water canbe shut off from a formation at the bottom of a well or water shut ofi'from entering by the top of a well. It is furthermore used to Shut gasin a well, to plug abandoned wells, and for various purposes that areobvious to a well driller.

The primary object of my invention is the provision of positive'and'reliable means, as hereinafter set forth, for securing a plug in awell, especially in a manner that permits of its removal.

Another object of this invention is to provide a plug that isconstructed somewhat upon the principle of a swab, the plug embodying aneXpansible member that insures a non-leakable connection between theplug and the well casing, when the member is expanded.

A further object of this invention is to accomplish the above results bya mechanical construction that is simple, inexpensive to manufact-ure,easy to manipulate, and highly eicient for the purposes for which it isintended.

With the above and other objects in View,

the invention resides in a vnovel construction,'

combination and arrangement of parts to be hereinafter specificallydescribed and then claimed.

Reference will now be had to the drawings' wherein like numerals ofreference designate corresponding parts throughout the several views, inWhich- Figure l is a vertical sectional view of a plug in accordancewith this construction, illustrating the same in a retracted position inthe casing of a well. Fig. 2 is a similar view showing the plug in anexpanded position. Fig. 3 is a horizontal sectional view taken on thelines 111-111 of Fig. 1. Fig. 11 is a similar view taken on the lineIV-IV of Fig. 1. Fig. 'is a plan of a plug support. Fig. 6 is aperspective view of a slip holder, and Fig. 7 is a perspective view of aplug body, partly broken and partly in sect-ion.

rlhe reference 1 denotes a bull plug or anchoring device and attached tosaid plug is a coupling l2 upon the upper end of which is screwed acoupling sleeve 3.

4: denotes a circular plug support having concentric nipples 5 and 6,the former being detachably mounted in the coupling sleeve 3.

7 denotes a heavy collar that is screwed on the nipple 6, and screwedinto the upper end of the collar 7 is a tubular exteriorly screwthreaded stem 8 that has the end thereof tapered, as at 9 and providedwith transversely alining openings 10. Ar ranged upon the circularsupport 1 is an expansible plug 11, preferably made of rubber, said plughaving a longitudinal bore 12 providing clearance for the stem 8. Thebore 12 has the lower end thereof enlarged, as at 13 to provideclearance for the collar 7 and the upper end of the bore 12 is enlargedto provide a conical shaped seat 14.

15 denotes a conical shaped slip holder in the form of a shell that ismounted upon the seat 111. The upper inner walls of the holder are screwthreaded, as at 16 and screwed into said holder is the dependingexteriorly screw threaded collar 17 of a cap 18 that is mounted upon theupper end of the holder and the plug 11. The collar 17 has an opening 19providing clearance for the tubular stem 8.

20 denotes a plurality of slips that are equally spaced within theconical shaped holder 15, said slips having the inner faces thereoftoothed or threaded, as at 21 to engage the threaded surface of thetubular stem 8. Surrounding the tubular stem 8, between the slips 2O andthe collar 17 is a coiled compression spring 22 that retains the slipsnormally in a lowered position in the holder 15 and said slips inengagement with the periphery of the tubular stem 8.

23 denotes a letting in nipple that is connected to the upper end of thestem 8 by a small metal rivet 24 that is arranged transversely in thenipple 23, said rivet extending through the opening 10 of the stem S.This rivet is preferably made of copper and is adapted to be sheared orbroken, as will hereinafter appear.

the upper end of placement.

In operation, the plug is lowered into the easing 25 of an oil well inthe position shown in Fig. l, that is, with the plug 11 retracted andthe stem 8 connected to the nipple 23 by the soft metal rivet 24.Immediately upon the bull plug 1 resting upon the bottom of the wellhole, the weight of the nipple 23 and its connections is sufficient toshear the soft metal rivet 24, whereby the end of the nipple 23 willrest upon the cap 18. The weight of the Inipple 23 and its connection issufficient to longitudinally compress the plug 11 and thereby expand theplug as illustrated in Fig. 2, whereby the periphery of the plug willengage the inner walls of the casing or tubing 25. lVith the walls ofthe plug 11 in engagement with the walls of the casing or tubing 25 anon leakable connection is established and it is impossible for a liquidor gas to pass between the plug 1l and the walls of the casing or tubing25, consequently thelower end of the casing or tubing is sealed. As theplug l1 is longitudinally compressed and laterally expanded the slipholder 15 is lowered, consequently the slips are allowed to eX- pandthrough the medium of the inclined lwalls of the holder 15 and thecompression spring 22, said slips obtain a fresh purchase upon theperiphery of the tubular stem 8 and thereby lock the plug 11 againstcontraction. These slips 20 serve functionally as locking members asbest shown in Fig. 2 and the plug is firmly held against accidental dis-To remove the plug 11 from the casing 25, a suitable tool (not shown) islowered into the casing or tubing and the tubular stem 8 jarred orunscrewed from the collar. When the stem 8 is released from the collar 7the plug 11 immediately contracts and can be removed. Suitable ishingtools can then be employed for removing the elements 1 4 to 7 inclusive.

It is thought that the operation and utility of the plug will beapparent without further description and while in the drawing there isillustrated a preferred embodiment' of my invention, it is to beunderstood that the structural elements are susceptible to suchvariations and modicatons as fall within the scope of the appendedclaims.

What I claim is 1. A plug of the type described comprising an anchoringdevice, a. plug support connected thereto, a stem connected to saidsupport, an expansible plug surrounding said stem, a slip holderarranged the upper end of said plug and surrounding said stem, springpressed slips arranged in said holder and retained normally inengagement with the periphery of said stem, and a nipple connected tothe upper end of said stem and adapted to be detached to expand saidplug.

2. 'A plug of the type described, comprising a support, a stem connectedthereto, an expansible plug surrounding said stem and resting upon saidsupport, slips arranged in the upper end of said plug and normallyengaging the periphery of said stem, and a nipple connected to the upperend of said stem and adapted to be detached to expand said plug.

3. A plug of the type described comprising a support, a stem carriedthereby, an expansible plug surrounding said stem and resting upon saidsupport, a nipple detach-- ably connected to the upper end of said stem,means located in the upper end of said plug to lock said plug in anexpandedposition.

4. A plug of the type described comprising a support, a stem detachablyconnected to said support, an expansible plug surrounding said stem andresting upon said support, a slip holder arranged in the upper end ofsaid plug, slips arranged in said holder and adapted to engage theperiphery of said'stem, and a nipple connected to the upper end of saidstem and adapted to be detached to engage the upper end of said plug andexpand the same.

In testimony whereof I -afx my signat-ure in the presence of twowitnesses.

HUGH L. MCLAUGHLIN.

Witnesses:

JOHN A. LAsH, LEWIS H. KELLY.

